1. Field
The invention relates to video format conversion. More particularly, the invention relates to combining deinterlacing and frame rate decimation for video format conversion.
2. Background
In the 1990s, television technology for representing and transmitting video moved from using analog methods to digital methods. A well known process in video format conversion is Telecine, which is the process of transferring a motion picture film (e.g., a 24 frames-per-second movie) into a digital video format (e.g., a 60 fields-per-second National Television Systems Committee (NTSC) video). The word Telecine is derived from a combination of the words “television” and “cinema.” Telecine enables a motion picture, captured originally on film, to be converted to a video format so that it can be viewed using standard video equipment such as computers and televisions. Hence, distributors and producers of motion pictures can release their films on video using Telecine.
Reverse or inverse Telecine is used to convert the digital video format to the motion picture film format. The inverse Telecine process involves converting a 60 fields-per-second progressive video to a 24 frames-per-second movie. Some benefits of the inverse Telecine process include high-quality non-interlaced display on compatible display devices and the elimination of redundant data for compression purposes. The inverse Telecine process, however, does not allow for the conversion of a 60 fields-per-second interlaced video to a 24 frames-per-second movie.
The conversion of a 60 fields-per-second interlaced video to a 24 frames-per-second movie involves two main steps. The first step is to deinterlace a 60 fields-per-second interlaced video to a 30 frames-per-second progressive video. The second step is to decimate the 30 frames-per-second progressive video to a 24 frames-per-second movie.
The conversion process described above has two main drawbacks. First, the decimation process produces jitters in the video because 24 is not a divisor of 30. The jitters cause an unpleasant viewing experience for the viewer. Second, the deinterlacing process is a computational intensive algorithm that includes motion compensation based techniques. Therefore, there is a need for efficient and innovative systems and methods for converting a 60 fields-per-second interlaced video to a 24 frames-per-second movie.